<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			var group = [[1,2,3,4].[5,6,7,8],[9,10,11,12]]
			console.log(group[0])
		</script>
	</body>
</html>
